The invention relates to a rotary anode x-ray tube comprising an anode assembly which is mounted by magnetic bearings and means for conducting current from the rotary anode to a stationary anode supply circuit.
A rotary anode x-ray tube of this type is described in U.S. Pat. No. 3,878,395. In the case of this rotary anode x-ray tube, the anode is supported for rotation by means of a magnetic bearing, which positions the anode assembly axially and radially without contact, the anode assembly drive motor including magnetically-soft material at the part of the anode assembly surrounded by the drive stator for driving the rotary anode, and the tube envelope having further electric windings at the exterior thereof for cooperation with additional magnetically-soft material of the rotary assembly to provide the bearing support for the rotary anode. In the case of this known rotary anode x-ray tube, for the conduction of the anode current, a mechanical contact is provided between a shaft rotating with the anode and a stationary portion. In the case of this contact, brief interruptions can occur which result in sparking. In addition, metal abrasion occurs.